testing-strategies

Test coverage targets vary by code type: critical code requires 100% coverage, business logic 90–100%, utilities 80–90%, and UI components 70–80%. These targets ensure high quality while accounting for practical constraints in different code layers.

Use a standardized directory structure that separates test types: unit tests for isolated functions, integration tests for component interactions, and end-to-end tests for full workflows. This structure improves maintainability and makes test suites easier to navigate.

Apply a structured test case pattern: happy path tests verify normal behavior, edge case tests check boundary conditions, error case tests validate error handling, and special case tests cover context-specific scenarios. This pattern ensures comprehensive coverage.

Unit tests validate individual functions in isolation, integration tests verify component interactions, and end-to-end tests confirm full workflows work together. Use all three: unit tests catch logic bugs early, integration tests surface interaction issues, end-to-end tests verify user-visible behavior.

Yes, the coverage targets and test case patterns are framework-agnostic and apply across multiple testing frameworks and languages. The strategy focuses on what to test, not the specific tools used to test it.

Mocks isolate the code under test by replacing external dependencies. Use mocks in unit tests to test logic independently, and rely on real integrations in integration tests to verify actual component behavior. This balance catches both logic and interaction bugs.